You are not currently logged in.
Access JSTOR through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Ancestry of the Coralline Algae
J. Harlan Johnson
Journal of Paleontology
Vol. 30, No. 3 (May, 1956), pp. 563-567
Published by: SEPM Society for Sedimentary Geology
Stable URL: http://www.jstor.org/stable/1300291
Page Count: 6
You can always find the topics here!Topics: Algae, Sporangia, Genera, Ancestry, Thallus, Cell growth, Specimens, Fossils, Evolution, Geology
Were these topics helpful?See somethings inaccurate? Let us know!
Select the topics that are inaccurate.
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
Preview not available
Most of the Recent genera of coralline algae date back to the Late Cretaceous or Early Tertiary. Little is known regarding their ancestry. The view has been generally held that the ancestral stock was to be found in the Paleozoic family Solenoporaceae. The primitive genus Archaeolithothamnium was supposed to represent a transitional stage between the solenoporaceas and the more highly developed Recent genera. It is, therefore, highly interesting to note that some Pennsylvanian algae recently studied show structures much more closely allied to the Recent genus Lithophyllum than any known among the Solenoporaceae. These structures include well-defined hypothallic and perithallic tissues, a co-axial hypothallus, and conceptacles of sporangia. Other recent finds from Lower Pennsylvanian limestones include abundant debris of a form having structural features suggestive of articulated coralline algae. It is suggested that the separation of the two types of coralline algae (the crustose and the articulated) may date back to Paleozoic times, and that the two main groups of the crustose corallines (Lithothamnium-type and Lithophyllum-type) are equally ancient.
Journal of Paleontology © 1956 SEPM Society for Sedimentary Geology